Difference between rpm -i and rpm -U ?

[Gordon Messmer]

Dan Thurman wrote:
> 
> What is the difference between rpm -i and rpm -U ?

"-i" is the option for "install".  "-U" is the option for "uhh... do the 
right thing (usually)".

> If I have a bunch of rpm files and use -i, will it remove
> previous versions of packages or will it retain older packages
> and install the newer package on top?

It will install the package as long as there are no conflicts with 
existing packages.  If an existing package and the packages you are 
trying to install have some of the same files, for instance, rpm will 
not install the new package.

> I assume -U looks for older packages, removes it if found,
> and then installs the newer package?

Pretty much, yes.  You don't want to do that in the case of kernels, but 
for most everything else, you do.